Toy calculator



R. A. STEVENSON.

TOY CALCULATOR.

APPLICATION FILED. FEB. 6, 1922.

1,438,144. Patented Dec. 5,1922

WITNESSES: WM MM mm f/Tp S'UR mm.

Patented 5,1922. U

UNITED STATES PATENT OFFICE.

nonnn'r A. s'rnvnnson, or mcnsrnn, onr'o.

. TOY CALCULATOR.

Application filed February 6, 1922. Serial No. 584,841.

To all whom it mayconcem:

Be it known that I, ROBERT A. STEVENSON,- a citizen of the United States, and a resident of Lancaster, in the county of Fairfield and State of Ohio, have invented a new and Improved Toy Calculator, of which the following is a description, reference being had to the accompanying drawings, which are a part of this specification.

This invention relates to improvements in toy calculators wherein a number wheel is revolved for the purpose of making arithmetical calculations.

The object of my invention is to provide a device which, by musing children and arousing their interest, will help in teaching the principles of arithmetic.

More particularly, I seek to produce a toy device of this character which may be used for adding, multiplying, subtracting or dividing and which at the same time will be so simple in construction that a child. will' be able to understand its operation.

A further object is to make a toy calculator which havin no intricate or delicate parts may be sub ected to rough handling and not be easily broken.

My invention is shown in the accompanyin drawings in which similar numerals in icate similar parts. I

-Fi ure 1 is a front elevation of the toy calcu ator as it would appear held before the operator.

Fi re 2 is a cross-section on the line 2-2 of Figure 1 looking in the direction pointed by the arrows.

Fi re 3 is an elevation of the supporting meml r.

Fi re 4 is an elevation of the number whee Referring first to Figures 1, 2 and 3, the supporting member 5 is provided with a slot 6 serving as a result slot. A pair of curved portions are provided on opposite sides of the supporting member 5, as indicated in Fi ures 1 and 3, and numerals from 1 to 10 inc usive are arranged in a circling manner upon these curved portions. The'su porting member 5 is further provided with edge ortions 7, 8, which act as finger stops. Klear these finger stops I have placed the legend Stop, as indicated in Figures 1' and 3.

A journal in 9 extends through the supporting member 5. Mounted. upon this ournal pin is a number wheel 10 provided as shown in Figure 4 with a row of numerals which in this articular instance run from 0 to 48 inclusive. This wheel is provided with teeth 11 which extend beyond the curved portions on the sides of the supporting member. By aid of these teeth and the' V-notches between the teeth the operator may turn the wheel in either of two directions.- Each of the teeth 11 on the wheel 10 is in spaced relation to each of the numerals upon the oppositely disposed curved portions of the supporting member 5. Each of the numerals on the wheel 10 is so placed as to be registered one at a time through the slot 6 as the wheel is turned.

Two narrow slots 12 and 13 are cut in the supporting member 5, as shown in Figures 1, 2 and 3. A circle 14 is made upon the tions of it are always visible through the slots 12, 13. Thus, it will be seen that by turning the Wheel 10 in either direction the circle changes its position in relation to the slots 12, 13, and gives the appearance of eyeballs rollin back and forth in the slots.

I In descriiing the method of using the device for making calculations I will first explain how it ma be used for adding or multiplying. The evice is turned into such position that the supportin member?) faces the operator as indicated 1n Figure 1. If it happens that the result slot 6 indicates a result previously found, the operator first desires to clear the slot so as to cause it to register 0. In order to do this he places his finger in a notch between two of the teeth 11 and turns the wheel 10 in either direction until a sin le 0 is re stored in the result slot. This fieaves the evice ready for either adding or multiplyin Accordin to Figure 1, the ri ht-hand si e of the ca culator is used by t e operator for addition and multiplication. For example, to add together 4, 8 and 7, he places his finger in the V-notch opposite the numeral 4 and rotates the wheel until his finger arrives at the legend Stop. Next, leaving the wheel 10 in the position he now finds it he goes back and places his finger op osite the numeral 8 and turns the wheel as fore until his finger reaches the legend Stop. Then he places his finger opposite the numeral 7 and makes a movement of the wheel until his fin r again arrives at the legend Stop. This one, the slot 6 will display the numeral 19.

1 so that 39 is registered in the slot.

in a clockwise direction until his finger arrives at the legend Stop. Repeating this three times he essentially multiplies 9 by 3 so that the slot 6 will indicate a result of 27 To use the device for subtracting or dividing, the operator uses the left-hand side of the calculator. For example, to subtract 9 from 42, the number wheel is turned in either direction until the numeral 42 is made to appear in the slot 6. This done, the operator places his finger in the V-notch opposite the numeral 9 upon the left-hand side of the device and pulls down to the legend Stop, thus turning the wheel 10 in a counter-clockwise direction. The number 33 now appears in the slot.

To divide, the number to be divided is first made to appear in the slot. For example, to divide 39 by 8, the wheel is turned The finger is placed opposite the numeral 8 upon the left-hand side of the calculator and pulled down to Stop. This operation is repeated, each time going back and placing the finger opposite 8. The operator mentally counts the times which this operation can be made before a numeral smaller than the divisor, in this case 8, appears in the slot. In this example, when he has pulled down four times the numeral 7 will appear, therefore he makes no more operations as he hfas7the correct result-4 with a remainder o It will be seen during the above calculations that the combination of the circle 14 with the slots 12, L3 will produce the efiect of eyeballs movin amusing the chil device. p

It is possible. for a number of children,

that is operating the each provided with-one-of these calculators,

back and forth, thus to make up games and contests to see which one can add, subtract and divide a series of numbers the quickest, which can be the most accurate, etc, etc.

I am aware that calculators of this character have been patented which maybe used for addition or multiplication but my improvement c0nsists,'principally, in providing the means whereby the device may be used, also for subtraction and division.

Therefore, what I claim as my invention, 1s

1. In a device for teaching arithmetic to children having a supporting base plate provided with a result slot, a group of numerals adjacent to one edge thereof, and a rotatable number wheel carried by the base plate containing an annular row of numerals arranged in consective "order adapted to appear one at a time in rear of said result slot, means for attracting the attention of children to said device consisting of an annular deslgn on said number wheel in ec-' centric relation to the axis thereof, said supporting face plate having a pair of diametrically aligned elongated openings disposed therein arranged at equal distances from the pivot point of said number wheel through which the circular design is adapted to appear.

2. In a device for teaching arithmetic to children, asupporting base plate shaped to simulate the appearance of a head of a figure and having a pair of elongated openings formed therein defining eyes, a dial disposed in rear of the face plate, a pivot for the dial carried by the face plate and an eccentrically disposed circular design disposed on the dial adapted to appear in rear of said openings, the dial and face plate having cooperating calculating means disposed thereon.

R. E. STEVENSOIt, F. A. Smvanson. 

